Mapping mountains from space with GOCE


Mount Everest
 



 
Traditional method of surveying. The GOCE (Gravity field and steady-state Ocean Circulation Explorer) derived model of the geoid will serve as a global reference for studying the topography of the Earth.

GOCE
 
ESA's first Earth Explorer Core mission GOCE (Gravity field and steady-state Ocean Circulation Explorer) will measure high-accuracy gravity gradients and provide global models of the Earth's gravity field and of the geoid. An improved gravity-field map will provide insight into the physics and dynamics of the Earth's interior and an accurate global geoid model will contribute to an improved understanding of ocean circulation, which plays a crucial role in energy exchanges around the globe and hence climate. This mission will also lead to a greater insight into sea-level change and to a global unification of height systems.

The geoid
 
The GOCE (Gravity field and steady-state Ocean Circulation Explorer) mission will measure high-accuracy gravity gradients and provide a global model of the Earth's gravity field and of the geoid. The geoid (the surface of equal gravitational potential of a hypothetical ocean at rest) serves as the classical reference for all topographical features. The accuracy of its determination is important for surveying and geodesy, and in studies of Earth interior processes, ocean circulation, ice motion and sea-level change.


 
Referencing airborne gravity measurements with GPS. Combinations of different geodetic techniques are necessary in order to obtain the required stability, consistency and accuracy of the reference frames. Full exploitation of GOCE (Gravity field and steady-state Ocean Circulation Explorer) data will probably rely on ground-based and airborne gravity measurement techniques, as well as other geodetic techniques such as GPS, SLR (Satellite Laser Ranging) and VLBI (Very Long Baseline Interferometry).


 
Airborne gravity measurements are an efficient way of mapping the Earth's gravity field with high spatial resolution. However, the GOCE (Gravity field and steady-state Ocean Circulation Explorer) mission will provide a global map of the gravity field.



Release date: 14 February 2008